/* passTCP.cpp - passiveTCP */
#include <winsock.h>
SOCKET     passivesock(const char *, const char *, int);
/*------------------------------------------------------------------------
 * passiveTCP - create a passive socket for use in a TCP server
 1
 See page 107 for a description of Algorithm 8.1.

 *------------------------------------------------------------------------
 */
	SOCKET
passiveTCP(const char *service, int qlen)
{
	return passivesock(service, "tcp", qlen);
}





/* - passivesock */
#include <stdlib.h>
#include <string.h>
#include <winsock.h>
void errexit(const char *, ...);
u_short   portbase = 0;      /* port base, for test servers        */
/*------------------------------------------------------------------------
 * passivesock - allocate & bind a server socket using TCP or UDP
 *------------------------------------------------------------------------
 */
	SOCKET
passivesock(const char *service, const char *transport, int qlen)
{
	struct servent     *pse;     /* pointer to service information entry  */
	struct protoent *ppe;   /* pointer to protocol information entry*/
	struct sockaddr_in sin; /* an Internet endpoint address       */
	SOCKET         s;  /* socket descriptor             */
	int       type;    /* socket type (SOCK_STREAM, SOCK_DGRAM)*/
	memset(&sin, 0, sizeof(sin));
	sin.sin_family = AF_INET;
	sin.sin_addr.s_addr = INADDR_ANY;
	/* Map service name to port number */
	if ( pse = getservbyname(service, transport) )
		sin.sin_port = htons(ntohs((u_short)pse->s_port)
				+ portbase);
	else if ( (sin.sin_port = htons((u_short)atoi(service))) == 0 )
		errexit("can't get \"%s\" service entry\n", service);
	/* Map protocol name to protocol number */

	if ( (ppe = getprotobyname(transport)) == 0)
		errexit("can't get \"%s\" protocol entry\n", transport);
	/* Use protocol to choose a socket type */
	if (strcmp(transport, "udp") == 0)
		type = SOCK_DGRAM;
	else
		type = SOCK_STREAM;
	/* Allocate a socket */
	s = socket(PF_INET, type, ppe->p_proto);
	if (s == INVALID_SOCKET)
		errexit("can't create socket: %d\n", GetLastError());
	/* Bind the socket */
	if (bind(s, (struct sockaddr *)&sin, sizeof(sin)) == SOCKET_ERROR)
		errexit("can't bind to %s port: %d\n", service,
				GetLastError());
	if (type == SOCK_STREAM && listen(s, qlen) == SOCKET_ERROR)
		errexit("can't listen on %s port: %d\n", service,
				GetLastError());
	return s;
}
